Much More Than Meets the Eye

MUCH MORE THAN MEETS THE EYE!!!

This was the heading that heralded the release of the all new MGC 6 cylinder sports car in Roadster and GT form 40 years ago on the 15thOctober 1967.

Whilst the headline was intended to reflect the hidden features and power of the new car it could also sum up the enormous ‘behind the scenes’ complexity in both the engineering and company management that had to be overcome during its development.

The MGC is a unique MG. The large capacity straight six cylinder three litre motor, the torsion bar suspension and its reputation at the time of being the fastest production MG built at Abingdon set it apart from other models.

At its release the MGC received a mixed reception from the press. Complaints included its similarity to the MGB, poor handling with a strong understeer and the ‘character’ of the engine. Nothing wrong with the straight line speed it was just the problem of going around corners!

Today the MGC is in demand and has a small but strong following of enthusiasts who have continued the development of the car since its release, stiffer torsion bars, modified higher gear steering racks and advance lower profile tyre technology combined with a large array of engine improvement options has produced the Grand Touring car that the original team at Abingdon had intended in the first place. It is a pity that it took 40 years!

Let’s go back to the beginning;

The MGC was not the exact car MG would have liked to produce but was the result of constraints / compromises within the broader BMC organisation.

In the early 60’s the Abingdon factory was producing the MGB Roadster and GT, the Midget/Sprite models, the Austin-Healey 3000 (The ‘Big Healey’) and of all things the Morris Minor Estate Cars and Vans!

BMC were looking to rationalise production and with the ‘Big Healey’ coming to the end of its life the BMC planners decided to build a bigger engine MGB as a replacement for the Healey.

The main problem was engineering, whilst everyone agreed there was a great deal of space under the bonnet of the MGB and plenty of air space in front of the four cylinder engine, any ‘engine transplant’ would have to be achieved without destroying weight distribution and handling. But what engine was the problem.

The Engine;

In 1964MG’s Syd Enever had looked at the possibility of a more powerful MGB. The best existing engine at the time was the Australian built ‘Light six’ 2,433cc which was simply a 1622cc B-Series unit with two extra cylinders.

An engine was obtained and a prototype developed within the existing bonnet shape of the MGB but with substantial modification to the front suspension to fit the longer and taller engine.

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However by the time the MGC project was given the formal go ahead it was clear this engine was not going to be produced in the UK. A series of existing engines available within the BMC group were considered and rejected for various reasons, finally BMC had decided that a ‘new’ C-series straight six engine would be developed for the entire BMC 3.0 litre demands.

This engine was essentially an extensive re-design of the current C-Series with some key requirements. It had to be physically smaller, considerably lighter and take into account the various exhaust pollution limitations being proposed around the world, in particular the North American market and as a more refined motor would be equipped with a seven-bearing crankcase.

Unfortunately the end result was a 2,912cc engine that was only 20lb lighter than the previous C-Series and still weighing in at 567lb, some 209lb heavier than the MGB four cylinder engine, with a saving in length of only 1¾ inches on the old C-Series motor!

The Body Shell;

In a classic ‘left hand v right hand’ situation, when the ‘new’ engine was presented to the MG engineers the bulk and weight of it had a far reaching effect on the structure of the car.

Visually to look at an MGC there appears to be little difference to the MGB except for the light alloy bonnet shape with an overall raised profile to fit over the radiator and a bulge to provide clearance for the forward of the two SU carburettors.

However under the skin the changes are extensive, because of the bulk and length of the engine (whose front ended up several inches ahead of the front wheels) the MGB’s cross members could not be retained and a wholesale re-design of the front suspension was required.

New inner wheel arches were designed and mated to a massive new U shape front suspension cross member designed to swoop under the engine and carry the forward engine and front suspension mountings.

The front suspension is unique and not related to any other MG. The MGC uses two-piece upper and lower forged wishbones, longitudinal torsion bars and telescopic dampers. The upper and lower wishbones and the telescopic dampers all pivoted from the new cross-member.

All of this front end re-design required new chassis side members and new forward floor panels to allow for the rear end of the torsion bars to be anchored to an adjustable pivot at the side of the gearbox/propeller shaft tunnel.

Also to allow for the first time the option of a Borg Warner automatic gearboxwhich was bulkier than the manual gearbox a more spacious ‘tunnel’ was fitted to all later cars.

Performance;

It was decidedto only fit 165-15in HR rating Dunlop SP41 radial ply tyres to the MGC.

With this small area of rubber on the road it was inevitable that given the much heavier front end, greater steering effort and understeer would occur.

Probably the engineers could have fixed this with revised front suspension geometry and larger profile tyres but financial constraints prohibited this at the time.

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Their only effort to improve steering effort was to fit a lower geared steering and reduction in castor in the front suspension geometry which gave a greater impression of sluggish feel in the handling.The final front/rear weight distribution for the MGC was 55.6/44.4 (as against the MGB 52.5/47.5)

The gearbox was the standard MGB four speed manual with synchromesh on all gears, optional overdrive on third and fourth was extra.The Borg Warner 35 automatic was also available.

The ‘new’ engine was smooth with the seven bearing crankshaft and produced excellent torque of 170lb ft/3,400 rpm. It was rated by MG at 150bhp/5250rpm. However the heavy fly wheel and very little low speed torque gave the engine a reluctance to rev and top end power. General comment on release was that the engine “is smooth and flexible, but lacking in sporting characteristics”

Yet for all this it was very fast and was/is an excellent cruising car over long distances.

The launch October 1967;

Given the generally negative press attitude to BMC at the time, BMC’s own financial status and the compromises that had been required to develop the MGC little wonder that the press took a negative view to this new sports car that was supposed to be a replacement for the ‘Big Healey’.

Universal complaints about the cars poor handling understeer and lack of differentiation to the MGB did not help the launch.

The interior of the car was very similar to the latest MGB Mk11 fit out.

There were many differences between the left hand drive North American cars and those produced for the domestic market, including dual braking system, different cylinder heads, inlet & exhaust manifolds and carburation.

At the launch the new MGC sold in the UK for;

MGC Tourer1,102 pounds

MGC GT1,249 pounds

Austin Healey 3000 Mk 111,126 pounds

Triumph TR5 P11,212 pounds

The MGC Production 1967 to 1969;

During the production phase of the MGC there were many subtle changes to the car and engine, all of which helped the performance of the car, but during this period BMC merged with Leyland and the British Leyland Motor Corporation was formed.

The implication of this was the influence of Triumph orientated management into BMC and in particular the Triumph Stag project.

Given the initial poor press and the inability/desire for BMC to promote the improvements made to the MGC, particularly during 1968, demand for the MGC began to wane and by 1969 the writing was on the wall, further regulations in America for the a 1970 model and the desire for British Leyland to rationalise their business conspired to end production of the MGC, with the last car a GT American version completed on the 18th September 1969.

In all 8,999 MGC’s were produced although the quirks of mass-production have the chassis numbers going up to 9102.

The split was almost 50/50 with 4,542 Roadsters and 4,457 GT’s being produced.

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The MGC Competition Cars;

The BMC competitions department were involved from an early stage in the development of the MGC and were able to fit into production six special light alloy bodies in 1967 prior to the release and sale of the MGC to the public.

To reduce weight while retaining strength these bodies had the entire floor pan and stress-carrying members in pressed steel while the skin panels and much of the superstructure were light alloy. The front and rear wheel arches were given substantial flares to give clearance for the larger section wheels and tyres to be used.

With the expected 200 plus bhp being available from a race tuned 3 litre engine the body shells had to be stiff, using the light allow panels meant that only the GT version of the MGC could provide the structural strength required. Front and rear bumpers were also removed.

The engine had an aluminium cylinder head (this alone reduced the weight by 20lb) with three dual choke Weber carburettors and full-flow racing exhaust manifold. The cast iron cylinder block with enlarged cylinder bore increased capacity to 2968cc, the fly wheel was lightened and overall these engines produced over 200bhp at 6,000rpm.

Three experimental all-alloy engines were also built and although records have been lost it is believed these had been used in at least one of the final competition cars.

Four wheel Girling disc brakes replaced the front disc/rear drum setup of the standard production cars.

Light Alloy Minilite wheels were used to take the substantially larger racing tyres.

After racing at Sebring these special MGC racing cars were given the title of MGC-GTS, where the S stands for Sebring and whilst these cars only appeared in four events over two years,they acquitted themselves well and with their distinctive look are today known to almost every MG enthusiast.

After 1969;

The real development started after production finished as enthusiasts around the world started to experiment and develop improvements to their cars.

This was initially assisted by the working relationship that had developed between Downton Engineering Works and University Motors, one of London’s principle MG dealerships.

Even while the MGC was still in production Downton had developed and marketed a number of performance enhancement to the standard production MGC which by 1969 had evolved into three stages of performance enhancement.

When production ceased at Abingdon around 150 MGC’s remained unsold and still in stock. University Motors made an offer for the remaining stock and took delivery between September and November 1969 and marketed them as ‘University Motors MG Specials’. While the vast majority of the cars were only treated to some re-trimming and special paint work many were performance enhanced by installing various stages of the Downton Conversions, some to a very high degree.

The MGC Today;

In Australia today there believed to be just over one hundred MGC’s in various stages of repair and many fine examples of well sorted out road cars up to high performance racing cars can be seen.

Given that there were no MGC’s imported and sold by dealers these have all been privately imported at some stage in their life from either the UK or from North America and converted to right hand drive.

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Steve Foldhazey from the NSW MG car club has attempted over the years to record all the known MGC’s in Australia. This is somewhat a moving target however the numbers are roughly;

Roadster UK20

Roadster USA14

GT UK45

GT USA26

Total =105

They are evenly spread across the Eastern states and South Australia with some example also in WA and TAS

The most common modifications carried out is to up-rate the torsion bars and

Ifdesired fit a higher geared steering rack.

Add to this the use of wider section tyres which contrary to what you might think actually reduces the steering effort and improves road holding. The standard wheel rim will take 185 x 70 R15 or a 195 x 60R15 tyres, this does not necessitate any bodywork modifications if the springs and suspension rubbers are in good condition except to perhaps turn up the lip under the wheel arch if the wheel touches. Just the simple matter of running approx. 5 psi extra in the front to rear tyres will improve the handling of the car.

There is a large range of potential engine and body modifications that are only limited by you budget, with a number of specialists able to enhance the cars performance right up to developing an MGC Sebring replica if required.

Today the MGC is recognised as a great classic and is no longer the maligned car at its launch; that bonnet bulge indicates something special.

Even in its basic form with modern tyres it is a great touring car that will travel all day without stress

In Victoria, the MG Car Club has at least 17 MGC’s on their register however there is usually only three to four cars regularly seen at club events and at the annual Concourse.

Nationally at the annual Easter National MG Car Club Meeting the maximum in recent time has been 11 cars.

Peter Morgan November 2006

References;

Classic and Sports Cars October 1994

MGC – Abington’s Grand Tourer, Graham Robinson 1996

MG World June/July 2001

Practical Classics September 2001